Heat a pan and add oil or vegan butter. Once, it's hot enough, add and fry cumin seeds, green chilies, ginger, garlic, onions, poppy seeds, bay leaf, cinnamon, cloves, cardamom, and cashews.
Fry for 1-2 minutes. Then add chopped tomatoes, garam masala, paprika, turmeric, tomato ketchup, sugar, salt, and dried fenugreek leaves.
Cook till the tomatoes turn soft and pulpy. Take it off the flame and allow it to cool down. Discard the bay leaf and cinnamon stick.
Transfer all the contents to a blender and blitz to make a smooth puree. Add 1/4 cup of water if needed.
Alternatively, you can also use a hand blender to make a puree.
Pass this puree through a sieve. Do not throw away the pulp.
Transfer the makhani puree to the same pan and bring to a boil.
Add vegan cream and give it a good mix. Check the taste and add more seasoning if necessary.
The consistency of this Vegan Makhani sauce should be thick and creamy. Do not thin it down. Transfer it to a bowl and keep it aside for now.